<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>3_react生命周期(新)18</title>
</head>
<body>
    <div id="test"></div>
    <!-- 引入react核心库 -->
    <script crossorigin src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <!-- 引入react-dom，用于支持react操作DOM -->
    <script crossorigin src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
    <!-- 引入babel，用于将jsx转为js -->
    <script type="text/javascript" src="https://unpkg.com/babel-standalone@6.26.0/babel.js"></script>
    <script type="text/javascript" src="https://unpkg.com/prop-types@15.6.2/prop-types.js"></script> 
    <script type="text/babel">
        
        //创建组件
        class Count extends React.Component {
    
            //构造器
            constructor(props) {
                console.log('Count---constructor');
                super(props)
                //初始化状态
                this.state = {count: 0}
            }
    
            //加1按钮的回调
            add = () => {
                //获取原状态
                const {count} = this.state
                //更新状态
                this.setState({count: count + 1})
            }
    
            //卸载组件按钮的回调
            death = () => {
                ReactDOM.unmountComponentAtNode(document.getElementById('test'))
            }
    
            //强制更新按钮的回调
            force = () => {
                this.forceUpdate()
            }
    
    
            //组件挂载完毕的钩子
            componentDidMount() {
                console.log('Count---componentDidMount');
            }
    
            //组件将要卸载的钩子
            componentWillUnmount() {
                console.log('Count---componentWillUnmount');
            }
    
            //控制组件更新的“阀门”
            shouldComponentUpdate() {
                console.log('Count---shouldComponentUpdate');
                return true
            }
    
            //组件将要更新的钩子
            UNSAFE_componentWillUpdate() {
                console.log('Count---UNSAFE_componentWillUpdate');
            }
    
            //组件更新完毕的钩子
            componentDidUpdate() {
                console.log('Count---componentDidUpdate');
            }
    
            render() {
                    console.log('Count---render');
                    const {count} = this.state
                return (
                    <div>
                        <h2>当前求和为：{count}</h2>
                        <button onClick={this.add}>点我+1</button>
                        <button onClick={this.death}>卸载组件</button>
                        <button onClick={this.force}>不更改任何状态中的数据，强制更新一下</button>
                    </div>
                )
            }
        }
    
        //父组件A
        class A extends React.Component {
        //初始化状态
            state = {carName: '奔驰'}
    
            changeCar = () => {
                this.setState({carName: '奥拓'})
            }
    
            render() {
                return (
                    <div>
                        <div>我是A组件</div>
                        <button onClick={this.changeCar}>换车</button>
                        <B carName={this.state.carName}/>
                    </div>
                )
            }
        }
    
        //子组件B
        class B extends React.Component {
        //组件将要接收新的props的钩子
            componentWillReceiveProps(props) {
                console.log('B---componentWillReceiveProps', props);
            }
    
            
    
            render() {
                console.log('B---render');
                return (
                    <div>我是B组件，接收到的车是:{this.props.carName}</div>
                )
            }
        }
    
        //渲染组件
        ReactDOM.render(<Count/>, document.getElementById('test'))
    </script>
        
</body>
</html>